Almost everywhere you look, people are talking about ultra-processed foods. Are they bad for our health? Should we be cutting back? What actually are ultra-processed foods anyway? Nutrition research can be tricky to wade through at the best of times, so we wanted to try and cut through some of the confusion and find out what the experts are saying when it comes to ultra-processed foods.
What are ultra-processed foods?
While the number of headlines on this topic seems to have skyrocketed in recent months, the term has been in use in nutrition and dietetics circles for a while. When it comes to the general public, however, it’s fair to say there’s been some mixed messaging.
The British Nutrition Foundation (BNF) commissioned a survey of UK adults in 2021. At that time, 70 percent of the respondents had never heard the term “ultra-processed foods” before, a number that may well be different if the survey were to be repeated today.
When it came to correctly categorizing foods as ultra-processed or not, the majority were unable to do so for several items that you probably have in your weekly shopping basket.
“There’s an increasing amount of research on ultra-processed foods and health, and the term is being used more than ever. But most people still have not heard of the term and are not clear about what it includes,” said Sara Stanner, Science Director at the BNF, in a statement.
The food we eat can be broadly divided into four groups using a classification system called NOVA, first proposed in 2009.
Unprocessed or minimally processed foods are things like fruits and vegetables, raw nuts, seeds, meat – we’re talking ingredients in their natural states, which you might pick up to cook a meal from scratch at home. Some processing, such as pasteurization, is permitted to ensure that the items are safe to consume. Frozen veggies would also count as minimally processed, for example.
The next category is processed ingredients, such as butter, sugar, and salt. These are substances found in nature but that require slightly more processing than the previous category before we can use them.
Then we come to the processed foods. These are generally made by combining ingredients from the first two categories. Examples of processed foods include canned fish, freshly baked bread, and cheese.
Finally, the ultra-processed foods are those produced by combining multiple ingredients with additives like preservatives, flavorings, and stabilizers.
Some examples of ultra-processed foods will be unsurprising – things like potato chips, and some ready-to-heat products like instant noodles. However, many other foods that can be classified as ultra-processed under these definitions might come as a bit of a shock.
BBC Good Food lists a selection of products that can be ultra-processed, depending on how they are made. Infant formula makes the cut, as does mass-produced bread (due to additives like emulsifiers), breakfast cereals, fruit yogurts, and vegan meat alternatives. It was these types of products, many of which are part and parcel of people’s everyday diets, that caught out the respondents to the BNF survey.
Are ultra-processed foods unhealthy?
This is a really big question that gets to the heart of the debates on this topic. Some people champion the removal of any and all processed foods from our diets, while others say the picture has to be much more nuanced.
A new umbrella review, pulling together data from lots of previous systematic reviews on this topic, concluded that consumption of ultra-processed foods was linked to 32 different adverse health outcomes, including cardiovascular, metabolic, and even mental health. The authors of the review called for more research, including an assessment of “population based and public health measures to target and reduce dietary exposure to ultra-processed foods.”
On the face of it, it sounds alarming – if these foods could be having such a broad impact on human health, surely we should make every effort to remove them from our diet, right?
Some experts certainly agree that this is an urgent problem.
“This analysis which includes almost 10 million people should be a call to governments around the world for a moratorium on [ultra-processed foods],” said Laureate Professor in Nutrition and Dietetics Clare Collins, who was not directly involved in the work.
Collins pointed out that the research the review relies upon is observational, “which means cause and effect cannot be proven and that the research evidence gets downgraded, compared to intervention studies.” But an intervention study would not be an easy sell to an ethics committee: “The problem is that it is not ethical to do an intervention study lasting for many years where you feed people lots of [ultra-processed food] every day and wait for them to get sick and die.”
Other prominent commentators echo this view. Dr Chris Van Tulleken is a UK-based medical doctor and TV presenter who has written and spoken extensively on the topic, including in his book Ultra-Processed People. Van Tulleken told the Guardian that the new review was “entirely consistent” with the “enormous number of independent studies which clearly link a diet high in [ultra-processed food] to multiple damaging health outcomes including early death.”
But there are also those who remain unconvinced.
While the review demonstrates the massive acceleration in research into this topic during the last decade, in a comment for Science Media Centre, Registered Dietician and Senior Lecturer Dr Duane Mellor pointed out, “It is important to note, just because there is a lot of research does not necessarily mean that there is a lot of quality in the research, meaning reviews are only as good as the research they are based on.”
Mellor also hit on another facet of this debate, which we touched on previously – if so many foods are classed as “ultra-processed”, can they all be equally dangerous to health?
“Given that some ultra-processed foods such as sweetened drinks and processed red meat have been linked with increased risk for decades, and bread especially wholegrain bread (which can still be classed as ultra-processed) has been associated with a reduced risk of disease, suggests that NOVA classification is too broad.”
And commenting on the BNF survey back in 2021, Stanner made the same point: “Many foods that would be classified as ultra-processed may not be recognised as such and, while many ultra-processed foods are not healthy options, this isn’t always the case.”
Should we be eating less ultra-processed food?
As mentioned above, some have indeed argued that ultra-processed foods should – as far as possible – be eliminated from the human diet.
In a 2023 report, the Scientific Advisory Committee on Nutrition (SACN), which advises the UK government on these matters, took a more moderate view. It said that while some of the evidence for health risks was concerning, it was not possible to determine how much of that risk came from the ultra-processed foods themselves, and how much was a result of wider dietary and lifestyle patterns.
What we appear to be driving at here is that ultra-processed foods are only part of the overall picture, and not all ultra-processed foods are created equal. As ethnobotanist James Wong highlighted in a post on X, some convenience meals contain just about the same ingredients that you would use if you were to make the dish from scratch at home.
Commenters weighed in, adding that for many, convenience foods are a necessity due to disability, financial or time poverty, or a variety of other reasons that make demonizing these options unhelpful.
Ultra-processed foods make up a large proportion of Western diets – around 60 percent for US adults – so moving away from them is no simple task. Many individuals and organizations, including the authors of the most recent umbrella review, have addressed the need for further research to better understand how these foods might be impacting health.
The latest evidence doesn’t really change what experts have been advising for years when it comes to building a balanced diet. Many would agree that some ultra-processed foods can play a part in that – at least until we have more concrete evidence to the contrary.
“Some ultra-processed foods, such as confectionary, fried snacks, cakes and sugary drinks, are already recognised by nutrition professionals as foods to limit, however this does not mean that all processed foods should be demonized,” Stanner said.
And, in any case, Stanner added, it should not necessarily be down to the consumer themselves to radically alter their diet, in an environment where ultra-processed foods are often affordable and readily available.
“Looking at food labels, in particular at sugar, salt and saturated fat content, can be valuable in helping us to make healthier choices. In addition, we need to encourage food manufacturers to produce foods that are healthier, ensuring that healthier food choices are easier, more convenient and affordable for people to make.”
The study is published in the BMJ.
